1. Field of the Invention
The present invention broadly relates to a coating composition which may be used with printable (e.g., paper) webs. The present invention also broadly relates to printable (e.g., paper) webs treated on one or both sides with the coating composition to impart benefits such as, for example, improved ink dry time and gloss. The present invention further broadly relates a method for treating one or more sides of a printable (e.g., paper) web with the coating composition.
2. Related Art
In a conventional calendered papermaking process, the fibrous web from the press roll section may contain from about 32 to about 45 wt. % solids. These solids may include wood pulp and/or synthetic fibers along with various additives such as sizing agents, binders, fillers, pigments, etc. The print quality of such calendared papers, as well as other properties of the papers, such as brightness, opacity, paper smoothness, etc., may be improved by coating the paper with different coating compositions that include color solids. The coating composition used to provide these color solids may comprise a mixture of: (1) a coating color having pigment(s) such as clay, calcium carbonate, titanium dioxide, etc., (2) a binder or binders such as modified starch, styrene butadiene rubber, polyvinyl acetate, vinyl acrylic, polyvinyl alcohol, etc.; and (3) various functional additives such as dispersants, viscosity modifiers, crosslinking agents, lubricants, etc. The resulting mixture may be applied to the paper web at a solids content of, for example, about 40% or greater by weight.
These coated papers may be used for a wide range of products including packaging, art paper, brochures, magazines, catalogues, leaflets, etc. For example, these coated papers may be used in inkjet printing and recording processes. Ink jet printing and recording systems using aqueous inks are now well known. These systems usually generate almost no noise and may easily perform multicolor recordings for business, home and commercial printing applications. But conventional coated papers for inkjet printing may remain poor in balancing good print density, internal sizing (as measured by the Hercules Sizing Test or HST), color-to-color bleed, print sharpness, image dry time, gloss, etc. Accordingly, there is still a need to provide such high-performance functionality to coated papers useful in inkjet printing, especially those substrates having improve image dry time and gloss.